Suspension system for lighting fixtures



Nov. 5, 1968 w. F. SOULE SUSPENSION SYSTEM FOR LIGHTING FIXTURES Filed NOV. 10, 1966 5 Sheets-Sheet l INVENTOR:

WALTER FREDERICK SOULE BY:

Cal/aha? 7 War-man NOV. 5, 1968 w, souLE 3,409,262

SUSPENSION SYSTEM FOR LIGHTING FIXTURES Filed Nov. 10, 1966 1 3 Sheets-Sheet 2 m \l o o N 2 LL.

INVENTOR: WALTER FREDERICK SOULE Nov. 5, 1968 w. F. SOULE 3,409,252

SUSPENSION SYSTEM FOR LIGHTING FIXTURES Filed Nov. 10, 1966 3 Sheets-Sheet 5 FIG 6 55 R'V'SING I6 SWITCH SENSING. DEVICE FIG 7 INVENTORI WALTER FREDERICK SOULE.

61100410941 (9' Worm! United States Patent O ABSTRACT on THE DISCLOSURE This specification discloses a cable suspension system for use in association with lighting fixtures and thelike in which suspension cables are stored in loops extending around a system of pulleys, some ofthe pulleys being movable in unison so as to cause extension or retraction of the suspension cables in unison. andpennittinglowering and raising of the lighting fixtures or the like, and in afurther embodiment, also incorporates photo sensitive means which are responsive-to ambient light levels in a working areaso as to cause the lighting fixtures to be lowered or raised so as to maintain a predetermined lighting intensity at such Working surface.-

This invention relates to an adjustable and controllable suspension system for electrical lighting fixtures and the like.

The location and design of electrical lighting fixtures and the like, particularly for use in ofiices, factories and larger buildings, presents considerable problems from the viewpoint of'maintenan ce. The design and construction of such buildings 'u'sually incorporates highceilings or roofs requiring the lighting fixtures to be supported and suspended at a very considerable height above the floor. In such cases, access to'such lighting fixtures by maintenance personnel for cleaning and replacement of faulty equipment is diflicult and in some cases dangerous. In some cases a specially designed portable scaffolding must be erected within the building in order to reach the lighting fixtures. Working at such heights requires the use of various safety attachments which, if not used, can lead to injury or loss of life. In addition, such special equipment represents a considerable expense and in many cases replacement of burnt outlamps or fluorescent tubes is made only at infrequent intervals with the result that the quality of the illumination available in the building becomes substantially impaired over considerable periods of time.

Various proposals have been put forward for suspending such lighting fixtures and the like on wires together with means for winding the fixtures up and down, but such systems have generally speaking been unreliable, and in particular have not been suitable for use with the elongated rectangular lighting fixtures normally used for fluorescent lighting. In the case of such rectangular fixtures, it is necessary to provide two suspension wires in order to maintain the fixture level. However, the majority of winding systems as have been proposed, have been irregular in operation with the result that the lighting fixture became tilted out of the horizontal. In addition, such prior art suspension systems were generally speaking not suitable for use with batteries of lighting fixtures and frequently required the use of a separate winding system for each fixture.

The present invention therefore seeks to overcome the difficulties associated with the prior art suspension systems and to provide a suspension system for lamps and the like which is effective. and reliable in use over long periods of time without the requirement for adjustment or maintenance.

More particularly, the invention seeks to provide a suspension system having the foregoing advantages in which 3,409,262 Patented Nov. 5, 1968 a multiple battery of lamp fixtures or the like may be raised and lowered as a singlehnit;

More particularly, the invention seeks to provide the foregoing and other advantages wherein'the suspension system may be incorporated within the lighting fixture unit itself. i r

More particularly, the invention seeks to provide" a suspension system having the foregoing advantages wherein the suspensionsy'st'er'n may also be incorporated in a separate unit which may be permanently attached to the building.

Moreparticularly, the invention seeks to provide the foregoing and other advantages bythe provision of'a suspension 'syst'em'which may be adapted to provide variations in the level of illumination available in the working area of the building.

The inventiori'se'eks'to provide theforegoing and other advantages which will become apparent from the following description of the preferred embodiment of the invention by the provision off A cable suspension system for use with'electrical lighting fixtures and the like and comprising a mounting means; at least one pair of suspension cables having one end fastened in relation to said mounting means, the free ends of each said cable extending away from said mounting means; at least one pulley for each said' cable mounted in fixed relation to said mounting means; a pair of operating cables arranged parallel to one another and moveable in opposite directions to one another relative to said mounting means; a moveable pulley for each said suspension cable fixed to a' respective said operating cable and moveable therewith in opposite directions, and means for moving said operating cables. I

A preferred embodiment of the invention will now be described by way of example only with reference to the following drawings in which like reference devices refer to like parts thereof throughout the various views and diagrams and in which:

FIGURE 1 is'a schematic perspective illustration of'a battery of fluorescent electric lighting fixtures suspended from a portion of a building by a suspension system according to the invention;

FIGURE 2 is a top plan view of one of the lighting fixtures shown in FIGURE 1 cut open to reveal the suspension system according to the invention;

FIGURE 3 is a sectional end elevation along the line 33 of FIGURE 2;

FIGURE 4 is a sectional side elevation of a portion of the suspension system shown in FIGURE 2 along the line 4-4;

FIGURE 5 is a schematic top plan view of a further 'embodiment of the suspension system;

FIGURE 6 is a schematic perspective illustration showing the suspension unit attached to the building and permitting the lighting fixtures to be slung independently therefrom; and,

FIGURE 7 is a schematic circuit diagram of a further embodiment.

In FIGURE 1 a battery of fluorescent electric lighting fixtures are shown indicated as 10, 10a, 10b, suspended from any suitable point in a building such as the beam B by means of respective pairs of suspension cables or wires 11a, 11b, 12a, 12b, 13a, 13b etc. Within each of lighting fixtures 10, 10a, 10b etc. there is provided cable storage means (to be described in detail below) for the storage of cable 11a, 11b, etc. Such cable storage meansisoperated (in a manner tobe described below) by the endless cable 14 running axially along the length of each of the lighting fixtures 10, 10a, 10b etc. comprising the particular battery of lighting fixtures 10 which are to be operated in unison. At the exposed end 15 of lighting fixture 10 there is provided an electrical motor 16 and reduction gear 17 and drive pulley 18. At the exposed end 19 of the fixture 1012, assuming the fixture b to conztitute the other end of the battery of fixtures, there is' provided a free-running pulley or sheave 20 around which cable 14 passes for maintaining tension therein. Obviously, where manual operation is all that is desired any suitable remote switching means (not shown) may be provided for controlling the operation of motor 16. It is also de:irable from the viewpoint of safety and compliance with safety regulations to provide some form of positive braking means. Accordingly, braking means 21 is mounted on gear box 17 on the opposite side thereof from pulley 18 and comprises any standard form of spring operated break provided with a suitable electrical solenoid for releasing the same which may be wired in parallel with motor 16.

The cable storage means for storing cables 11a and 11b, 12a, 12b etc. is shown in more detail in FIGURES 2, 3 and 4. 'Cable 11a will be seen to be anchored'as for examp'e by bolt and extended therefrom along the length of fixture 10 and around movable pulley 31 back to fixed pulley 32 and upwardly around the vertically mounted pulley 33. Similarly, cable 11b will be seen to be anchored at bolt 34 and passes around movable pulley 35 back around fixed pulley 36 and upwardly around vertically mounted pulley 37. It will be noted that fixed pulleys 32 and 36 are fastened directly to the fabric of a lighting fixture 10. Vertical pulleys 33 and 37 are mounted on angle cross members 38 and 39 also faitened directly to the fabric of fixture 10 whereby to spread the load thereof and to avoid overstressing of the points of attachment thereto. Movable pulleys 31 and 35 are mounted on yokes 40 and 41. Yoke 40 is clamped to the upper portion of operating cable 14 and yoke 41 is clamped to the lower portion of cable 14 whereby upon movement of the cable 14 being procured by operation of motor 16 yokes 40 and 41 will be drawn towards or away from one another thereby extending or contracting cables 11 and 11a.

It will also be noted that the fixed pulleys 33 and 37 are located approximately on a common transverse axis with bolts 30 and 34 but spaced apart on the opposite side of fixture 10 therefrom to provide a clean pathway for movement of cable 14 and yokes 40 and 41 while maintaining the looped or doubled portion of cables 11, 11a in a common plane therewith to ensure free running thereof.

Operating cable 14 is guided into and out of lighting fixture 10 along upper and lower guide pulleys 42, 43, 44 and 45 located at either end thereof.

According to the embodiment of FIGURE 5, provision may be made for the storage of greater quantities of cable 11a and 11b by merely enlarging yokes 40 and 41 and providing a series of pulleys 31 and 35 thereon, the remaining members being essentially the same.

In some cases where greater aesthetic appeal is required such as in halls, offices and the like the embodiment of FIGURE 6 may be employed. In this case, the cable storage means is enclosed in a separate housing attached independently and permanently to a portion of the roof or ceiling such as beam B. A standard lighting fixture 51 is suspended from housing 50 by means of cables 11 and 11a which are stored on cable storage means housed with in housing 50 and is otherwise the same as has been described above except that of course cables 11 and 11a are led downwardly instead of upwardly Operating cable 14 passes through housing 50 and functions in the same way as before.

By means of the invention it is additionally possible to provide a system for automatically varying the illumination at floor or bench level to accommodate variations in daylight, by simply raising or lowering the lighting fixtures. According to the embodiment of FIGURE 7 a control system for movement of the lighting fixtures 10, 100, etc. may comprise the electric motor 16 (see FIG. 1) connected through a reversing switch 55 to a power source 56. Reversing switch 55 is controlled by a photo sensitive 4. device 57 preferably located at or near fioon'or berich level and adapted to sense light intensity andge'ne'ratir'iga control signal causing switch 55 to move to any one of three positions namely forward"stop-reyer'se thereby controlling motor 16 and causing upward oi downward movement of fixtures 10,100, etc.

The foregoing is a description of a preferred embodi mentof the invention'and is given here by way'of exam: ple only. The invention is notto be taken as limited toatiy of the specific'features'described but comprehends alls'tich variations as come within appended claims. A

What I claim as my invention'isz 1. A cable suspension system for: use withel ectric al comprising?" to one another and relative to said'mounting means I along predetermined parallel axes;

a moveable p'ulley for each said'sus'pensioii cable'aro'und" which said suspension cable runs in aloop" having two portions Which loop portions are at an angle to one another and to said operating cables; e'achjs'a'id' movable pulley being fixed to a respective'said oper-- ating cable and moveable therewith in oppositedirec *tions towards and away'fror'n its respective saidfixed pulley whereby to extend and retract said loop,

and means for moving said operating cables. 2. A cable suspension system as claimed 'in cla m'l wherein said fastened end of 'a said cable,"and said 're-' spective'fixed pulley and saidr'espective moveable-pulley are located in substantially a common plane. Y

3. A cable suspension system as claimed in claim 2 including a second fixed pulley for each said suspension cable mounted on said mounting means in a plane substantially normal to said common plane.

4. A cable suspension system as claimed in cla'm 1 including guide pulleys fastened to said mounting means at each end thereof for carrying said operating cables.

5. A cable suspension system as claimed in claim 1 including guide pulleys for said suspension cables attached adjacent to said mounting means in a plane substantially normal thereto and normal to the said axes of said operating cables.

6. A cable suspension system as claimed in claim 1 including braking means controlling the movement of said operating cables.

7. A cable suspension system as claimed in claim 1 including photo sensitive means located beneath said lighting fixtures for sensing the level of ambient light, and control means responsive to said photo sensi ive means to operate said operating cable movement means.

8. A cable suspension system as claimed in claim 1 including a housing for said pulleys attachable to a building, and openings in said housing in a horizontal lower face thereof for said suspension cables and openings in vertical end faces of said housing for said operating cables.

9. A cable suspension system for use with electrical lighting fixtures to cause said lighting fixtures to be raised or lowered to vary the level of ambient light in a work space, said system comprising; a mounting means; at least one pair of suspension cables having one end fastened in relation to said mounting means, the free ends of each said cable extending away from said mounting means; at least one pulley for each said cable mounted in fixed relation to said mounting means; a pair of operating cables arranged parallel to one another and movable in opposite the spirit and scope of the" 5 6 directions relative to one another and relative to said References Cited mounting means; a movable ulley for each said suspen- UNITED STATES PATENTS SlOIl cable fixed to a respective said operating cable and movable therewith in opposite directions; motor means 2,176,979 10/1939 Plat? 248'328 for moving said operating cables in opposite directions; 5 2,798,680 7/1957 Fafnngton et 248 317 XR photo sensitive means located spaced below said mounting 3035'804 4/1962 Wllson 248-328 XR means for sensing the ambient light in such space, and, control means responsive to said photo sensitive means ROY FRAZIER Pnmary Exammer' to operate said motor means. I. FRANKLIN FOSS, Assistant Examiner. 

